Rendering vertex colours from imported WRL object
Don’t panic. This will be easy. 
First off, that “row of icons” is the tabs of the Properties Editor, and is now on the side of that same editor. Things work generally the same way, except Blender Internal Render has been scrapped, so things in the Textures tab generally do not affect things in the Materials tab: You use shader texture nodes instead. The textures made in the Texture tab of the Properties Editor are for other purposes like compositing.
Secondly, you can input color into your material with the Vertex Color Node. If you do not know how to use material shader nodes, it’s time to learn. They are very intuitive, and both Cycles render and the new EEVEE render use them.
Refer to the blender manual at docs.blender.org under:

Editors -&gt; Properties
Rendering -&gt; Shader Nodes
...for more information.